Timer



"Aug. 5, 1952 H. N. uss 2,605,833

TIMER Fi ld Jan. 25, 1951 4 sheets-sheen n HUURS MINUTES OGLOCK cooKPERIQD FINISH TIME 1 Monitor HARVEY N BLISS M g aw 0 5, 1952 H. N. BLISS2,605,833

TIMER Filed Jan. 25, 1951 4' Sheefi-Sheet 3 I42 as /27 A75 /33 60 54 532 Snventor 3/ 37 36 HAR EY N BLIJS attorney Patented Aug. 5, 1952UNITED STATES PATENT OFFICE TIMER Harvey N. Bliss, Windsor, Conn,assignor to Veeder-Root Incorporated, Hartford, Conn, a. corporation ofConnecticut Application January 25, 1951, Serial No. 207,707

2i Claims.

This invention relates to timers, and more particularl to timeresponsive control mechanism which may be preset to sequentially performa plurality of operations at preselected future times.

Although timers constructed in accordance with thi invention may beutilized in many installations to perform various operations, the timerof this invention is particularly i well adapted for use with kitchenranges so as 'to enable the housewife to preset her range toautomatically commence and complete a cooking operation at chosen futuretimes, it being highly desirable that timers for kitchen ranges beprovided with simplified control devices so that the housewife can setthe range for automatic operation, under the control of the timer,without becoming involved in a series of complicated calculations oroperations to arrive'at the particularsetting she desires.

It is a general object of the present invention to provide a timer forkitchen ranges and the like which may be preset to automatically controla cooking operation of preselected duration to be completed at apreselected time.

It is a more particular object of this invention to provide a timer forkitchen ranges and the like which has separate indicators andindependent setting means therefor for directly indicating a selectedfinish time and for directly and separately indicating a cookingfperiodthereby requiring no calculations in presetting.

It is another object of this invention to provide a timer for cookingranges or the like with direct readin indicators showing a cookingperiod and a selected finish time with independent setting means foreach indicator which may be preset simultaneously or in any desiredsequence.

Still another object of this invention is to provide a timer for cookingranges or the like which may be preset with facility to visibly,indicate a selected automatic cooking period and to visibly indicate aselected fihishtime for the cooking period and which will indicateduring the cooking period the time remaining'to run.

A further object ofthe invention is to provide a new and improved systemof combining and correlating a clock mechanism, a switch con trolmechanism, and manually settable devices having indicating means to showthe selected positions of the clock mechanism at which the switchcontro1 mechanism will be functioned in terms of operating time andfinish time, whereby the combined apparatus is rendered completely thecorrelation and cooperation of the said mechanisms and devices is fullyautomatic.

Another object of the present invention is to provide in a device of thecharacter described an improved switch control mechanism which permitssensitive and accurate functioning of the switch and which isparticularly. adapted for use in the new and improved system of theinvention.

Other objects will be in part obvious, and in part pointed out more indetail hereinafter.

The invention accordingly consists in the features of construction,combination of elements and arrangementof parts which will beexemplified in the construction hereafter set forth and the scopeof'theapplication of which will be indicated in the appended claims.

In the drawings--- I Fig. l is a front elevational view of a timerconstructed in accordancewith this invention and which is particularlyadapted for use with an electric kitchenrange for automaticallycontrollin a cooking operation of the range at preselected future times.

Fig. 2 is atop plan view of the timer shown in Fig. 1.

Fig. 3 is a rear elevational view of the timer shown in the first twofigures.

Fig. 4.1 a vertical cross-sectional view taken as indicated generally bythe line 4-4 of Fig. 2 and viewedin the direction of the arrows there-Fig. 5 is a transverse sectional view taken generally as indicated bythe line 55 of Fig. 3 and viewed as indicated by the arrows thereon.

Fig. 6 is a fragmentary horizontal sectional View taken as indicatedgenerally by the line E-J of-Fig. 3 and viewed in the direction of thearrow thereon.

Fig. 7 is also a fragmentary horizontal crosssectional view taken aindicated generally by the line f!'l of Fig.3 and viewed in thedirection of the arrows thereon.

Fig. 8 is a diagrammatic view of the operating mechanism of the timershown in'oblique projection.

In the various views of the drawings, there is illustrated a specificembodiment of a timer constructed in accordance with the presentinvention which is particularly adapted for use in H connection with anelectric kitchen range for controlling the automatic operation of therange.

It will be apparent, however, that timers con structed in accordancewith the present invention are not limited for use with kitchen rangesand may be advantageously utilized in many other installations for timeresponsive control of the various operations. For instance, the timer ofthe present invention may be utilized to open or close valves atpreselected future times in any desired sequence or may be used to openor close electric switches to circuits which may incorporate variouselectrical appliances.

Referring now to the drawings in detail, the time controlled mechanismof this invention is disposed within a case indicated generally by thereference numeral suitable for mountin in any desired manner upon anelectric kitchen range (not shown). The case ID has a front wall Hprovided with a face plate l9 and supporting a clock face l2 havingconventional minute and hour hands I3 and I4, respectively, the clockbeing settable by means of a conventional knob id. The clock operatingmechanism shown in the drawings is of conventional construction drivenby a synchronous electric motor M having conventional field elements I 5and [6 (Fig. 3) and a coil H. The gear train 4| of the clock mechanismis also conventional and will be described in more detail later inconnection with other operating parts of the timer mechanism.

While an electric clock mechanism has been shown in the drawings, itwill be apparent from the following description that the clock mechanismmay be of the hand wound spring type or any other type which might bepreferred in a particular installation.

The wall I journals three setting shafts which are associated withmanually operable control knobs 20, 2| and 22. y The righthand controlknob 25 is connected to a setting shaft 23 for setting a minutes numberwheel 24 and an hours number wheel 25 visible through windows 26 in thewall I and plate I9 adjacent the control knob 29. The visible indicationon the number wheels 24 and 25 indicates the time at which the desiredcooking operation will be completed. This may be identified by suitableindicia such as oclock-Finish Time imprinted on the face plate l9adjacent and below the windows 26. When the knob is manipulated to setthe number wheels 24 and to the desired indication other elements of thetimer mechanism are also set in a manner to be described later.

The lefthand control knob 2| is connected to a setting shaft 2'! forsetting a minutes number wheel 28 and an hours number wheel 29 readilyvisible through windows 30 in the wall I] and plate l9 adjacent thecontrol knob 2|. The number wheels 23 and 29 indicate the cook period inhours and minutes, which, in the specific embodiment, is shown by theindicia Hours-Minutes-Cook Period imprinted on the plate I8 adjacent andbelow the windows 30. When the control knob 2| is manipulated toindicate the desired cook period in the windows 30 other devices of thetimer mechanism are set in a manner to be described later.

The centrally disposed control knob 22 is connected to a switch actuatorshaft 3| (Fig. 5) which may be set in one position to place the electricrange under the control of the timer mechanism for automatic operationand in another position to place the range in condition for manualoperation. The shaft 3| carries a disk segment 32 which bears theindicia Set On Off Man which are separately visible, dependin upon therotated position of the switch actuator shaft 3|, through a window 33located in the clock face |2 adjacent and above the numeral 5. Fornormal operation of the range, the indicia Man is visible in the window33 to indicatev that the range may be manually operated. To set therange for-automatic operation, the shaft 3| and control knob 22 isrotated until the indicia Set is visible in the window 33. Thereafter,the range is automatically controlled by the timing mechanism and issequentially operated to the On and "Off conditions which are indicatedby the corresponding indicia visible in'the window 33. As will bedescribed more particularly hereinafter, all that the operator need doto set the timing mechanism for automatic operation of the range is tomanipulate the control knobs 20 and 2| simultaneously or in any desiredsequence to place the selected indications of the finish time and cookperiod in the windows 26 and 30, respectively, and then set the switchactuator shaft 3| by means of the control knob 22 to Set position asindicated in the window 33.

By way of illustration, there has been shown in Fig. 1 of the drawings adesired finish time of twelve oclock and a cook period of 1 hr. 40 min.with the actuator shaft Set. This means that at 10:20 the automatic cookperiod will commence and the actuator shaft 3| will rotatecounterclockwise (as viewed in Fig. 1) so that the indicia On will bevisible in the window 33. At twelve oclock the 1 hr. 40 min. cook periodwill have been completed and the actuator shaft 3| will again rotatecounterclockwise so that the Off indicia will be visible in the window33.

A general description of the timing mechanism and its operation may bebest understood with respect to Fig. 8 wherein the elements arediagrammatically illustrated. The synchronous motor M has a pinion driveshaft 40 driving the conventional-gear train indicated generally by thereference numeral 4| which, in turn, drives a minute gear 42 having aminute hand shaft 43 and a drive pinion 44. The drive pinion 44 drives agear 45 and associated pinion 46 which, in turn, drives an hour gear 41and its associated hour hand shaft 48. It will be understood that thevarious gears and other elements of the timing mechanism are supportedor journaled by the case or frame H) in the manner shown in the variousfigures.

In accordance with the present invention the pinion 46, in addition todriving the hour gear 41 drives a power take-off gear 49 which carries abevel gear 50 for rotation therewith. The bevel gear 50 meshes with asecond bevel gear 5| which is freely rotatable on a shaft 58 secured bythe frame or case ID. The gear 5| is provided with a sleevelike hub 52which has fixed thereto a pawl-like pickup element or finger 53 forrotation therewith. As a result, the finger 53 is driven one completerotation by the clock mechanism every twelve hours. Also disposed on theshaft 56 and therefore concentric with the hub 52 is a gear 54hereinafter referred to as the timing gear. The timing gear 54 is freelyrotatable and axially slidable on the shaft 55. Ex-- tending outwardlyfrom one side of the timing gear 54 is a pin 55 which may be engaged bythe finger 53 whereby the timing gear 54 may be rotated by the clockmechanism. The timing gear 54 is urged in an axial direction toward thefinger 53 by a spring I34 extending between the frame I0 and an annularhub member I33 fixed to the gear 54. As a result, the gear 54 isnormally disposed so that the finger 55 is disposed in the path ofrotation of the finger 53 and will be rotated by the finger 53 when thefinger 53 is brought into contact with the pin 55 by the clockmechanism. On the other hand, the timing gear 54 may be slid axiallyaway from the finger 53 to remove the pin 55 from the path of rotationof the finger 53.

The timing gear 54 is in mesh wi-th'a wide gear 60 which comprises oneelement of a differential indicated generally by the reference numeral6|. The gear 56 is made sufficiently wide so that the timing gear 54remains in mesh therewith in either shifted position.

Turning .now to the differential 5|, gear 60 is freely rotatable about ashaft 62 and journals one end of a plurality of pinion shafts 63 equallyradially spaced from the shaft 62. The other ends of the pinion shaft 63are journaled in a disk 64 rotatably mounted on a shaft 65. The shafts63 carry intermeshing pairs of pinion gears .65 arranged so that theouter extremities of the pinions of each pair in mesh respectively withconcentric pinions 6'! and 58 integrally formed on shafts 62 and 65,respectively. The pinions 61 and 68 are formed on the opposed inner endsof the shafts 62 and 65 which carry gears 69 and 10, respectively attheir outer ends. As will be apparent, gear 60 may be driven throughdifferential 6| by either drive gear 69 or 10, or both, and this may beaccomplished either simultaneously or sequentially, a desired.Conversely, drive gear 69 or 19 may be driven by rotation of gear 60. Aspreviously mentioned, gear 66 is in mesh with timing gear 54 andtherefore the relative rotated position of timing gear 54 with respectto finger 53 can be varied by rotating either gear 69 or In, or both.Since finger 53 is operated by the clock mechanism, the rotationaldistance between finger 53 and pin 55 on timing gear determines theamount of time which will elapse before the differential is actuated bythe clock mechanism. When finger 53 engages with pin 55, the clockmechanism drives the differential through gear 66.

Differential driving gear 69 is connected with the finish time settingmechanism by a gear mounted for rotation with and on one end of a shaft16 which supports the finish time minutes number wheel 24 and hoursnumber whee1 25. The other end of the shaft I6 secures a bevel gear 11which is in mesh with a bevel gear 18 secured to the inner end of thefinish time setting shaft 23. Thus, manipulation of the control knob 20and finish time setting shaft 23 will drive the differential gearing 6|through the drive gear 69. At the same time the number wheels 24 and 25are set to the selected position within the windows 26 in the timer faceII, this for the reason that the minutes number wheel 24 is fixed to theshaft 16 while the hours number Wheel 25 is driven through conventionaltransfer mechanism by the minutes number wheel 24. In the embodimentshown, the minutes number wheel 24 bears two consecutive sets of indiciarunning from 00 to 50 in multiples of 19 consecutively. The hours numberwheel 25 is provided with indicia running from numbers 1 to 12,inclusive. Also in the embodiment shown, the transfer mechanismcomprises a mutilated pinion 89 rotatably mounted on a transfer pinionshaft 8| secured in the frame or case In. The mutilated pinion B9 isengaged by a locking disk 82 having suitable transfer teeth 32' on theminutes wheel 24 and, in turn, drives the gear 83 on the hours wheel 25.The arrangement is such that one complete revolution of the minutesnumber wheel 24 will rotate the hours number wheel 25 by two hours asrepresented by two digits on the hours number wheel 25.

The gear ratios employed, including those in the differential 6|, aresuch that when the shaft 16 is rotated one revolution corresponding to aperiod of two hours, as above mentioned, the time gear 154 will berotated revolution which is the distance traveled by finger 53 in thesame period, 1. e. two hours. The indicia on the number wheels 24 and 25are arranged so that the finish time appearing in the windows 26increases, i. e., indicate a later time when the shaft 16 is rotatedclockwise, as viewed in Fig. 8 of the drawings. When the shaft 16 isrotated clockwise the time gear 54 also is rotated in avclockwisedirection by the differential 6 I. Clockwise rotation of timegear 54 serves'to advance the pin 55 ahead of the finger 53 therebycausing the differential 6| to be driven in a reverse direction by theclock mechanism commencing at a later time, depending upon the extent towhich the number wheels, 24 and 25 are advanced. I

The finish time setting mechanism is provided with a .detent comprisinga spring arm 84 carried by the frame or caseifl and engageable in aplurality of cavities 85 in the outer side wall of the minutes numberwheel 24. There is one cavity 85 provided for each of the digitsappearing on the number wheel 24 so that the finish time indicator canbe accurately set in selected ten-minute increments. The .detent alsoserves to hold the differential drive gear 69 while the differential isbeing driven in either direction by the differential drive gear 10 or bythe timing gear 54. I 2

Differential drive gear 19 is connected with the cook period settingmechanism by a gear 99 which is secured to one end of a shaft 9| forrotation therewith. The other end of the shaft 9| secures a bevel gear92 which is in mesh for setting purposes with a bevel gear 93 secured tothe inner end of the cook period setting shaft 21. The shaft 9| isaxially shiftably supported by the frame or case IO so that the gears 92and 93 may be brought into mesh when the selected cook period isbeingset, and may be disengaged after being set for purposes and bymeans to bedescribed later. Spring I46 dis I posed between the frame andgear 96 normally urges the shaft 9| in a, righthand direction (as viewedin Fig. 6) to intermesh gears 92 and 93'. The gear is sufiiciently wideto remain in mesh with gear '10 regardless of the shifted position ofshaft 9|. Detent means comprising a ball 98 engageable inthe teeth ofthe bevel gear 93 and a spring 99 disposed within a cavity I90 (Fig. 6)in the frame In provides for accurate setting of the Cook Periodindicator in ten-minute increments.

The shaft 9| carries the minutes number wheel 28 and the hours numberwheel 29 for indicating the selected cook period in the windows 39 ofthe face The minutes number wheel is splined to the shaft 9| forrotation therewith and in the embodiment shown is provided with twoconsecutive sets of indicia ranging from 00 to 50 in steps of 10. Thehours number wheel ,29 of the cook period bears the hours indicianumbered from 1 to 5 and is driven by the minutes number wheel 28through a mutilated transfer pinion 94 rotatably mounted, on

a transfer pinion shaft 95 secured to the frame or case I9. The transferpinion 94 is engaged by a locking disk 96 having suitable transfer teeth96' carried by the minutes number wheel and by a driven gear 9'! carriedby'the hours number wheel. The arrangement is such that the hours numberwheel 29' is turned through two digits (hours) upon each completerevolution of the minutes numberwheel 28. The desired cooking time canthus be preset on the number wheels 28 and 29 and. be visible throughthe windows 30 by manipulation of the control knob 2|. The side of thenumber wheel 29"is provided with a lug IOI which is adapted to engagestops I02 and I03 supported by the casing I9. The stops I02 and'l03 areso located that the wheel 29 can be turned freely. to display thenumerals through 5 but cannot be turned directly from 0 to 5 or viceversa. In other words, rotation of wheel 29 is limited to less than afull revolution in either direction.

The gear ratios employed between the cook period setting mechanism andthe time gear 54 including the gear ratios of the differential BI, inthe embodiment shown, are exactly the same as those between the finishedtime setting mechanism, i. e. for each revolution of the shaft 9| thetime gear 54 is rotated of a revolution which corresponds to a period oftwo hours in both cases.

The indicia on the number wheels 28 and 29 are arranged oppositely tothat of the number wheels 24 and 25 with the result that the cook periodis increased by rotating the shaft 9I in a counterclockwise direction,as viewed in Fig. 8 of the drawings. Counterclockwise rotation of shaft9I drives the time gear 54 through differential 6| also in acounterclockwise direction. The result is that when the cook period isincreased, as shown by a higher set of numbers appearing in the window39, the time gear 54 is rotated so as to bring the pin 55 closer to thefinger 53, thus conditioning the apparatus for operation in a reversedirection by the clock mechanism commencing at an earlier time dependingupon the extent to which the number wheels 28 and 29 are advanced.

When the timer is assembled, the cook time setting mechanism, finishtime setting mechanism, differential 6| and time gear 54 are connectedso that, with the cook period indicators at zero and the pin 55 inengagement with the finger 53, the reading on the finished timeindicators is the same as the setting of the clock hands I3 and I4.Thereafter, these devices remain fully coordinated and complete accuracyof the timer is assured.

As will be apparent from the above description, the rotated position ofthe time gear 55 will always depend upon the algebraic sum of thesettings of the cook period setting mechanism and the finish timesetting mechanism, i. e. the distance of the pin 55 from the finger 53will always be equal (from a time standpoint) to the difference betweenthe time indicated by the clock hands I4 and I3 which fixes the positionof finger 53 and the finish time indicated by number wheels 24 and 25minus the cook period indicated by number wheels 28 and 29.

When the device is set in operation for automatic control of the rangeor other instrumentality, the first operation which takes place is theadvancement of the finger 53 by the clock mechanism until it engages thepin 55 on the time gear 54. Thereafter, the clock mechanism drives thetime gear 54 which, in turn, drives the gear 60 of the differential GI.Inasmuch as the shaft I6 is retained against rotation by the detent 84,the output of the differential is directed to shaft 9| of the cook timesetting mechanism with the result that the number wheels 28 and 29 arereturned to zero position in time with the clock mechanism. At the endof the operation, when the cook time period has been reduced to zero,the time gear 54 is shifted by mechanism to be described hereinafter soas to disengage the pin 55 from the finger 53.

Coming now to the manner in which the aforesaid relationship of the cookperiod setting mechanism, finish time setting mechanism, time gear 54,and finger 53 is utilized in accordance with the invention to control anassociated mechanism such as an electric range, it will be observed thata notched control disk I05 is fixed to shaft 65 for rotation therewith.The ratio of gears '19 and 99 is such that the shaft 95 makes one-thirdof a revolution for each complete revolution of the shaft 9|. In otherwords, the control disk I95 will make one complete revolution every sixhours, this being also the maximum setting of the cook period indicatingnumber wheels 28 and 29. The control disk I95 has thirty-six notches I99cut in its outer periphery with the result that the disk I95 is rotatedone notch for each ten-minute period shown on the cook time indicatingwheels 28 and 29. One of the notches I99 which is indicated at I95 iscut relatively deep compared with the remaining notches I96 for thepurpose hereinafter described.

As previously mentioned, the rotated position of the actuating shaft 3|is utilized to determine the condition of operation of the associatedapparatus, such as a kitchen range. The shaft 3| is biased in acounterclockwise direction by the spring 34, which is secured at one endto the frame I0 and at the other end to a collar 35 fixed to the shaft3|. The spring 34 also serves to urge the shaft 3| outwardly, i. e. tothe right as viewed in Fig. 5 of the drawings, to the axial positionshown. The collar 35 is slotted at 36 to slidably receive a key 3? onthe segment dial 32 to permit the shaft 3| to move axially withoutdisplacing the dial 32. The dial 32 is rotatably received in a recess 38in the wall I I which is covered by the face plate I8 and is thusrestrained against movement in a direction axially of shaft 3I.

Disposed on the internal end of the actuating shaft 3I are a pair ofspaced apart arms I98 and I99 having ears I01 and III, respectively, atthe outer ends thereof and extending therefrom at an angle ofapproximately As best shown in Fig. 2 of the drawings, the arms I99 andI99 are so located when shaft BI is in its normal axial position thatthe arms will have a path of rotation at right angles to the plane ofdisk I and just outside the periphery thereof. However, the ears I91 andI I I, being turned inwardly toward the disk I05, will normally engageagainst the side of the timing disk I05 adjacent the periphery thereof.The arms I98 and I99 are preferably made of light spring materialwhereby they are relatively flexible in a plane axially of the shaft 3|.Since the righthand edges of the ears I91 and HI are beveled asindicated at IIO, the engagement of the ear I97 or III with the disk I95will not prevent turning of the shaft in a clockwise direction, this forthe reason that the arm I08 or I99, as the case may be, will be cammedand thus flexed outwardly to cause dis- 9 engagement. However, upon thereverse rotation of shaft 3|, the flat'edges of the ears I01 and III arebrought into engagement with the disk I and thus remain in holdingengagement. In'the Set position of shaft 3| the arms I08 and I09 aremoved, to the position shown in Figs. 2 and 6 of the drawing, i. e. withthe ear I01 of arm I08 engaged against disk I05. Engagement of ear |01with disk I05 retains shaft 3| in the Set position against the bias ofspring 34. a

The length of theear I01 is such that, when it is brought intoengagement with the edge of disk I05 and'disk I05 is rotated to bringone of the notches I06 into registry therewith, the ear I01 will passthrough the notch thereby releasing shaft 3| for rotary movement underthe influence of spring 34.

The effective length of the arm I08 is such that the ear I01 will engagethe disk I5 slightly in advance of oneof the notches I03 when the cooktime indicators 28 and 29, are accurately set in one of the selectiveten-minute settings thereof. Accurate positioning of the number Wheels28 and 29 is insured, as previously mentioned, by the detent 9B.

As'soon as any driving force is transmitted to the differentialtl byreason of the pickup of the pin 55 by the finger 53 the disk I05 willbegin to rotate; Slight movement of the control disk I05 causes a notchI06 to be brought into registry with the ear I01 on the arm I08permitting the ear I01 to pass through the notch, thus permittingcounterclockwise rotation of the actuating shaft 3| to the On position.

The ear I on the arm I09 is made somewhat longer than. the ear I01 sothat it cannot pass through any of the notches I06 except the deep notchI06. Accordingly, when shaft 3| is released for counterclockwisemovement by reason of. ear I01 passing through one of the notches I06,rotation is, thereafterhalted by, engagement of ear I'II withthe side ofdisk I05, thus. fixing the On? position of shaft 3|. The axial positionof disk I05 on the shaft 65 is such that the deep notchltlfi is broughtinto registry with the ear III when the cook time indicating wheels 28and 29 have been returned to the zero position. When this conditionoccurs the ear III is free to pass through the notch I06, thus releasingthe actuating shaft 3| for further rotation to the Off position. The Oilposition of shaft 3| is fixed by the engagement of finger I I2 onstationary lug II3.

It thus will be seen that when the selected cook period is set on thenumber wheels 28 and 29 the relatively deep notch I06 will be rotatedaway from registry with the path of movement of the ear I I I byanamount which is equal from a time standpoint to the desired cook time.At the same time, as previously mentioned, the time gear 54 is rotatedrelative to the'finger 53 in an amount depending upon the selected cooktime and selected finish time. [As a result, the pin 55 of the time gear54 is picked up by the finger 53 to cause reverse driving of thedifferential 6| by the clock mechanism at the position of the clockwhich difiers from the 'finish time by the amount of the cook. periodselected. Almost immediately upon engagement of the pin 55 by the finger53 resulting in rotation of the disk I05, a notch I0 is brought. intoregistry with the finger I01 permitting the actuating shaft to move tothe On position. Then, as thedifierential 6| is further driven by the"clock mechanism and 10 the number wheels 28 and'29 are returned tozero, the deep notch I06 is brought into registry with the ear III, thusreleasing the shaft 3| for movement to the "Off position. At thismoment, of course, the finishtime appearing on the number wheels 24and,25 corresponds exactly with the clocktime. In order to utilize themovements of shaft 3| to control an'associated apparatus, the shaft 3|has fixed thereto a cam I25. In the specific embodiment shown in thedrawings, cam I25 is utilized to operate a switch I connected by meansof terminals I2| forfcontrolling the heating elements of the range withwhich the timer is being employed. The switch I20 is of conventionalconstruction and may be provided, by way of example, with a pivotalcontact arm I21 fulcrumed by a pin I28 intermediate its ends and adaptedto cooperate with stationary contacts I29. A spring I26 is utilized tobias the arm I21 to closed. position. The outer end of the terminal armI21 engages one arm of a bell crank I22 which, in turn, engagesthe camI25.

The cam I25 is so designed that the switch I25 is held in open positionat all times except when the shaft 3| is in the On orManual positions.

The cam I25 also operates a second bell crank I which is pivotallymounted on a shaft |3| secured, bythe frame IOand which has a bifurcatedarm I32 embracing the hub I33 on the timing gear 54. The arrangement issuch that upon rotation of the actuator shaft 3| to the Off or Manualpositions the cam I25 will rotate the .bell crank I30-to shift thetiming gear 54 axiallyaway from the finger 53 whereupon the pin 55 isremoved from the path of rotation of the finger 53. This insures thatthere will be no interference of the finger 53 with the positioning ofthe time gear 54 in either rotated direction by the Finish Time and CookTime setting mechanisms, nor will the position of the time gear 54 beoperated by the finger 53 when the device is not in use.

Also fixed to the shaft 3| is a cam I44 for operating a bell crankhaving arms MI and I42 and pivoted at I43. The arm MI is adapted toengage against the side of the gear 90. The cam I44 is so designed thatwhen the shaft 3| is turned to the Set or On positions, the shaft 9| ismoved axially so as to disengage the gears 92 and 9-3. This removes theCook Time setting mechanism from control by. the knob 2| so that theknob'2l andits detent 98 will place'no load on the driving mechanismduring automatic operation of the range.

In order to move the shaft 3| from Off position to Manual'position, itis necessary for the operator to thrust the shaft 3| inwardly againstspring 34 to cause the finger I I2 to clear the lug II3, whereupon theshaft 3| is released for the required additional turning movement to theManualflposition. The Manual position is fixed by abutment of the fingerII 2 against a final stop which, for convenience, in the particularembodiment shown comprises the adjacent end of hell crank I30. Aspreviously mentioned, turning the shaft 3| to Manual position closes theswitch I20 and thus places the range under the. sole control of themanually operated switches of the range.

It thus will be seen that there has been provided in accordance with theinvention a time responsive control mechanism which is fully automaticin operation, which can be preset with simplicity and ease, which isfully accurate and foolproof in operation, and which clearly and simplyidentifies the stages and conditions of operation at all times.

As many changes could be made in the above construction and manyapparently widely different embodiments of this'invention could be madewithout departing from the scope thereof, it is intended that all mattercontained in the above description or shown in the accompanying drawingsshall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the language used in the followingclaims is intended to cover all of the generic and specific features ofthe invention herein described and all statements of the scope of theinvention which, as a matter of language, might be said to falltherebetween.

I claim as my invention:

1. A timer comprising a plurality of setting means, a clock mechanismhaving a driving element, a driven element adapted to be advancedrelative to said driving element, and differential gearinginterconnecting said driven element, and said'setting means.

2. A timer comprising a plurality of setting means, a clock mechanismhaving a rotatable driving element, a rotatable driven element adaptedto be driven by the driving element in predetermined relatively rotatedpositions thereof, and differential gearing interconnecting said drivenelement and said setting means.

3. A timer comprising a plurality of manually operable setting means, acontrol member connected to one of said setting means for movementtherewith, a clock mechanism having a driving element, a driven elementadapted to be driven by the driving element in predetermined relativepositions thereof, and differential gearing interconnecting said drivenelement and said setting means.

4. A timer comprising a plurality of manually operable setting means, acontrol member connected to one of said setting means for move menttherewith, a clock mechanism having a rotatable driving element,.adriven element rotatably settable relative to, said driving element andadapted to be driven by the driving element in predetermined relativelyrotated positions thereof, and differential gearing interconnecting saiddriven element and said settingmeans.

5. A timer comprising a plurality of manually operable setting means,independent indicating means for each of said setting means to indicatethe positions thereof, a control member connected to one of said settingmeans for movement therewith, a clock mechanism having a drivingelement, a driven element movable relative to said driving element andadapted to be driven by the driving element in predetermined relativepositions thereof, and driving means including a differential betweensaid driven element and said setting means.

6. A timer comprising a pair of aligned shafts, differential gearingconnecting said shafts including a sun gear on each of said shafts, aplanetary supporting gear, and planetary pinions carried on saidsupporting gear and meshing with said sun gears, manually operablesetting means for said aligned shafts, a clock mechanism having arotatable driving element, a gear meshing with said planetary supportinggear and rotatable coaxially with said driving element, and meansforming a driving connection between the driving element and saidcoaxial gear in predetermined relatively rotated positions thereof.

7. A timer comprising a first indicator shaft, a second indicator shaft,a settable driven element, a continuously maintained positive drivingconnection between the indicator shafts and the driven element includinga differential, a clock mechanism having a time responsive drivingelement, and means forming a driving connection between the driving anddriven elements at a predetermined relatively rotated position thereof.

8. A timer comprising a plurality of manually operable setting means,independent indicating means for each of said setting means to indicatethe positions thereof, a control member connected to one of said settingmeans for movement therewith, means for actuating an associatedmechanism responsive to said control member, a clock mechanism having arotatable driving element, a driven element rotatably settable relativeto said driving element and adapted to be driven by the driving elementin predetermined relatively rotated positions thereof, and differentialgearing interconnecting said driven element and setting means.

9. In a time responsive switching device, a rotatable control disk,switch actuating means responsive to said rotatable control disk, firstsetting means for setting said control disk in selected rotatedpositions, time controlled driving means, a rotatable driven member,means forming a driving connection between said driven member anddriving means in one relatively rotated position thereof, second settingmeans, means for rotating said driven member relative to said drivemember selectively by said first and second setting means, and means forpreventing movement of said second setting means while said control diskis rotated by said first setting means or said driven member.

10. In a time responsive switching device, a rotatable control disk,switch actuating means responsive to said rotatable control disk, anindicator for showing the position of said control disk, first settingmeans for setting said control disk in selected rotated positions, timecontrolled driving means, a rotatable driven member, said driving meanshaving means engageable with said driven member in one rotated positionrelative to said driven member, second setting means, means for rotatingsaid driven member relative in said drive member selectively by saidfirst and second setting means, a second indicator for showingthe'rotated position of said driven member relative to said drivemember, and means for preventing movement of said second setting meanswhile said control disk is rotated by said first setting means or saiddriven member.

11. In a time responsive switching device, a rotatable control disk,switch actuating means responsive to said rotatable control disk, firstsetting means for setting said control disk in selected positions, timecontrolled driving means, a rotatable driven member, said driving meanshaving means engageable with said driven member in one rotated positionrelative to said driven member, second setting means, differentialgearing interconnecting said driven member with said first and secondsetting means whereby said driven member may be rotated relative to saiddrive member selectively by said first and second setting-means, andmeans for preventing movement of said second setting means while saidcontrol disk is rotated by said first setting means or said drivenmember.

12. In a time controlled switch, switch actuatsaid timing gear in onerotated position relative thereto, second setting means, differentialgearing interconnecting said timing gear to said control disk and saidsecond setting means whereby said timing gear may be rotated relative tosaid drive means selectively by said first and second setting means, andupon engagement of said timing gear by said drive means, said controldisk will be rotated to permit movementof said actuating arm to onposition, and means for preventing movement of said second setting meanswhile said control disk is rotated by said first setting means or saidtiming gear.

13. In a time controlled switch, switch actuating means, a rotatablecontrol disk for controlling the switching movements of said actuatingmeans, said control disk having one rotated position relative to saidactuating means permitting movement thereof to switch opening position,first setting means for setting said control disk in selected positionsrelative to said actuating means, an indicator for showing the positionof said control disk, clock mechanism, a timing gear, rotatable drivemeans on said clock mechanism engageable with said timing gear in onerotated position relative thereto, second setting means, differentialgearing interconnecting said timing gear to said control disk and saidsecond setting means whereby said timing gear may be rotated relative tosaid drive means selectively by said first and second setting means andupon engagement of said timing gear by said drive means said controldisk will be rotated to one of a plurality of positions relative to saidactuating means permitting movement thereof to switch closing position,and meansfor preventing movement of said second setting means while saidcontrol disk is rotated by saidfirst setting means or said timing gear,

14. In a timer, the combination comprising a clock mechanism providedwith a rotatable driving element, a rotatable driven element mountedcoaxially with the driving element, means forming a driving connectionbetween the driven element and the driving element in a predeterminedrelatively rotated position of the driven and driving elements, a firstindicator shaft, indicating means for selectively indicating'a period ofoperating time operated by the first indicator shaft, 2. secondindicator shaft,-indicating means for selectively indicating a finishtime operated by the second indicator shaft, and driving means includinga differential between said driven element and said indicator shaftswhereby the rotated position of the driven element relative to saiddriving element is determined by the difference between the clock timeand the finish time minus the operating time.

15. A timer comprising a first setting means including an indicatorshaft, indicating means I on the shaft and a drive shaft, a secondsetting means including a second indicator shaft, second indicatingmeanson the second shaft and a second shaft, a differentialcouplingincluding a sun gear on each of said drive shafts,-and a drivegear on which are mounted planetary pinions in meshwithjsaid sun gearsyaclock mechanism provided with a rotatable driving element, a gearmountedcoaxially with the driving element and in mesh with the drivegear of said differential coupling, means forming a drivin'g connectionbetween the last-named gear and the" driving element in one relativelyrotated position thereof, a switch operating mechanism and a rotatablecontrol member operatively connected for rotation with the first settingmeans, having means for functioning the switch operating mechanism at aninitial and final rotated position thereof.

16. A timer comprising a clock mechanism provided with a drivingelement, a driven element mounted coaxially with the driving element,means forming a driving connection between the driving element and thedriven element in a predetermined relatively rotated position of thedriving and driven elements, a first indicator shaft, indicating meansoperated by said shaft, gear means between said driven element and saidfirst indicator shaft including a differential arranged so that theindicating means may be operated in a subtracting direction as thedriven element is turned in the driving direction of the drivingelement, a second indicator shaft, indicating means operated by thesecond indicator shaft, means. connecting the second indicator shaft tothe differential whereby the said driven element may be turned in thedriving direction of the driving element as the last-named indicatingmeans is advanced, rotatable control means operated in response toturningof the first indicater shaft, and means settable for a first movement responsive to initial movement of the control means and a secondmovement responsive to movement of the control means to a positioncorresponding to zero position of the first indicating means.

17. A timer comprising a clock mechanism provided with a rotatabledriving element, a driven element mounted coaxially with the driv ingelement, means forming a driving connection betweenthe driven elementand the driving element in a predetermined relatively rotated positionof the driving and driven elements, a first indicator shaft, indicatingmeans operated by the first indicator shaft for selectively indicating aperiod of operating time,.a second indicator shaft, indicating meansoperated by the second indicator shaft for selectively indicating afinish time, driving means including aldifferential between said drivenelement and said indicator shafts whereby the rotated position of thedriven element relative to said driving element is determined by thedifference between the clock time and the finish time minus theoperating time, rotatable control means operated in responseto turningof the first indicator shaft, and means settable for a first movementresponsive to initial movement of the control means and a secondmovement responsive to movement of the control means to a positioncorresponding; to zero operating time. i i

i 18. A timer comprising a clock mechanism provided with a rotatabledriving element, a driven element mounted coaxially with the drivingelement, engageable means adapted to engage and form a drivingconnection between the driven element and the driving element in apredetermined relatively rotated position of the driving and drivenelements, a first indicator shaftQindicating means operated by the firstindicator shaft for selectively indicating a periodof operating "time, asecond indicator shaft, indicating means operated by the secondindicator shaft for selectively indicating a finish time, driving meansincluding a differential between said driven element and said indicatorshafts whereby the rotated position of the driven element relative tothe driving element is determined by the difference between the clocktime and the finish time minus the operating time, said operating timebeing zero when the driven and driving elements are interengaged and thefinish time is equal to the clock time, means for preventing turning ofthesecond indicator shaft through said differential, means forpreventing operation of the first indicator shaft during rotation of thesecond indicator shaft, means for releasing said engageable meansbetween the driven and driving elements during manual operation of saidfirst and second indicator shafts, rotatable control means operated inresponse to turning of the first indicator shaft, and means settable fora first movement responsive to initial movement ofthe control means anda second movement responsive to movement of the control means to aposition corresponding to zero operating time.

19. A timer comprising a clock mechanism provided with a rotatabledriving element, a driven element'mounted coaxially with the drivingelement, engageable means adapted to engage and form a drivingconnection between the driven element and the driving element in apredetermined relatively'rotated position of the driving and drivenelements, a manually operable first indicator shaft, indicating meansoperated by the first indicator shaft for selectively indicating aperiod of operating time, a manually operable second indicator shaft,indicating means operated by the second indicator shaft for selectivelyindicating a finish time, driving means including a differential betweensaid driven element and said indicator shafts whereby the rotatedposition of the driven element relative to the driving element isdetermined by the difference between the clock time and the finish timeminus the operating time, said operating time being zero when the drivenand driving elements are interengaged and the finish time is equal tothe clock time, means for preventing turning of the second indicatorshaft through said differential, means for preventing operation of thefirst indicat-or shaft during rotation of the second indicator shaft, a'rotatable control disk operatively connected to the first indicatorshaft, switch actuating means movable in one direction to sequentiallyperform a plurality of switching operations, means biasing the actuatingmeans in said one direction, a plurality of stops on said actuatingmeans sequentially engageable with said control disk during movement ofthe actuating means in said one direction, means on said control diskdefining a plurality of escapements for the first of said stops andmeans on said control disk defining an escapement for the second of saidstops, said last-named escapement being located for registry with thesecond of said stops when the operating time is zero. a

20. In a time responsive switching device, switch actuatingmeans-movable in one direction to sequentially perform a plurality ofswitching operations, means biasing the actuating means in said onedirection, a rotatable control disk, a plurality of stops on saidactuating means sequentially ,engageable with said control disk duringmovement of the actuating means in said one direction, means on saidcontrol disk defining a plurality of escapements for the first of saidstops, means on said control disk defining an escapement for the secondof said stops, time controlled driving means for said contol disk, andmeans for setting the control disk whereby upon initial rotation thereofthe first of said stops will escape said control disk to effect oneswitching operation of said actuating means and upon further rotation ofsaid control disk for a preselected period the second of said stops willescape said control disk to effect another switching operation of saidactuating means.

21. In a time responsive switching device, switch actuating meansmovable in one direction to sequentially perform a plurality ofswitching operations, means biasing the actuating means in said onedirection, a rotatable control disk, a plurality of stops of varyingform on said actuating means sequentially engageable with said controldisk, means on said control disk defining a plurality of notches toprovide escapement for the first of said stops only, means on saidcontrol disk defining a notch to provide escapement for the second ofsaid stops, manually operable means for setting the rotated position ofsa d control disk, time controlled driving means, and means for havingan adjustable time delay for interconnecting said driving means and saidcontrol disk whereby upon interconnection thereof the first of saidstops will escape said control disk to effect one switching operationand upon further rotation of said control disk for a preselected periodthe second of said stops will escape said control disk to effect anotherswitching operation of said actuating means.

22. In a time responsive switching device, switch actuating meansrotatable in one direction to sequentially perform a plurality ofswitching operations, means biasing the actuating means in said onedirection, a rotatable control disk having an axis of rotationtransverse of the axis of rotation of said actuating means, a pluralityof radially disposed and angularly related stops on said actuating meanssequentially engageable with the peripheral portion of said controldisk, said stops being of different length, means on said control diskdefining a plurality of relatively shallow notches about the peripherythereof providing an escapement for the first of said stops, means onsaid control disk defining a relatively deep notch on the peripherythereof providing an escapement for the second of said stops, manuallyoperable means for setting the rotated position of said control diskrelative to said actuating means, time controlled driving means, andmeans for interconnecting said driving means and said control disk at aselected future time whereby upon interconnection at said future timethe first of said stops will escape said control disk to effect oneswitching operation and upon further rotation of said control disk for apreselected period the second of said stops will escape said controldisk to effect another switching operation of said actuating means.

23. In a time responsive switching device, switch actuating meansmovable in one direction to sequentially perform a plurality ofswitching operations, means biasing the actuating means in said onedirection, a rotatable control disk, a plurality of stops on saidactuating means sequentially engageable with the peripheral portion ofsaid control disk during movement of the actuating means in said onedirection, means on said control disk defining a plurality ofescapements about the periphery thereof for the first of said stops,means on said control disk defining an escapement on the peripherythereof for the second of said stops, manually operable means forsetting the rotated position of said control disk, time controlleddriving means, means having an adjustable time delay for interconnectingsaid driving means and said control disk, and manually operable meansfor adjusting the lastnamed means whereby interconnection of said drivemeans and said control disk may be effected at a preselected future timeto immediately release the first of said stops to effect one switchingoperation of said actuating means and upon further rotation of saidcontrol disk for a preselected period the second of said stops will bereleased to effect another switching operation of said actuating means.

24. A timer for automatically controlling electric ranges or the likecomprising a switch, a switch actuator, a rotatable control disk forcontrolling the movements of said actuator, said control disk having aplurality of rotated positions relative to said actuator permittingswitch closing movement thereof and one position permitting switchopening movement, first setting means for setting said control disk inselected positions relative to said actuator, an indicator J meansselectively by said first and second setting means, manually operablemeans for placing said actuator in a set position for sequentialmovements to switch closing and opening positions under the control ofsaid control disk, whereby upon engagement of said timing gear by saidrive means said control disk will permit movement of said actuator toswitch closing position, a second indicator operable by said secondsetting means and showing the time when said actuator will move toswitch opening position, and means for preventing movement of saidsecond setting mean while said control disk is rotated by said firstsetting means or said timing gear.

HARVEY N. BLISS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,130,405 Andrews Sept. 20, 19382,166,872 Mayers 1- July 18, 1939 2,209,108 Briggs July 23, 19402,217,226 Lux Oct. 8, 1940 2,281,553 Bennett May 5, 1942 r 2,300,950 LuxNov. 3, 1942 2,310,527 Hutt Feb, 9, 1943 2,361,262 Candor Oct. 24, 19442,419,077 Isserstedt Apr. 15, 1947 2,557,464 Rambert June 19, 1951

